<template>
  <div>
    <!-- 面包屑导航 -->
    <el-breadcrumb separator-class="el-icon-arrow-right">
      <el-breadcrumb-item :to="{ path: '/home' }">首页</el-breadcrumb-item>
      <el-breadcrumb-item>商品管理</el-breadcrumb-item>
      <el-breadcrumb-item>参数列表</el-breadcrumb-item>
    </el-breadcrumb>
    <!-- 卡片试图 -->
    <el-card>
      <!-- 警告区域 -->
      <el-alert title="注意：只允许为第三级分类设置相关参数！"
                type="warning"
                :closable="false"
                show-icon>
      </el-alert>
      <!-- 选择商品区域 -->
      <el-row class="cat_opt">
        <el-col>
          <span>选择商品分类：</span>
          <!-- 选择商品的级联选择框 -->
          <el-cascader v-model="selectedKeys"
                       :options="catelist"
                       :props="{ expandTrigger: 'hover',label,value,chlidren }"
                       @change="handleChange">
          </el-cascader>
        </el-col>
      </el-row>
      <!-- tab页签区域 -->
      <el-tabs v-model="activeName"
               @tab-click="handleTabClick">
        <!-- 动态参数 -->
        <el-tab-pane label="动态参数"
                     name="many">
          <el-button type="primary"
                     size="mini"
                     :disabled='isBtnDisable'
                     @click="addDialogVisible=true">添加参数</el-button>
          <!-- 动态参数的表格 -->
          <el-table :data="manyTableData"
                    border
                    stripe>
            <!-- 展开行 -->
            <el-table-column type="expand">
              <template v-slot='scope'>
                <el-tag v-for="(item,index) in scope.row.attr_vals"
                        :key="index"
                        closable
                        @close="handleClose(index,scope.row)">{{item}}</el-tag>
                <!-- 添加的文本框 inputVisible:input的显示控制 -->
                <el-input class="input-new-tag"
                          v-if="scope.row.inputVisible"
                          v-model="scope.row.inputValue"
                          ref="saveTagInput"
                          size="small"
                          @keyup.enter.native="handleInputConfirm(scope.row)"
                          @blur="handleInputConfirm(scope.row)">
                </el-input>
                <!-- 添加属性按钮 -->
                <el-button v-else
                           class="button-new-tag"
                           size="small"
                           @click="showInput(scope.row)">+ New Tag</el-button>
              </template>
            </el-table-column>
            <!-- 索引行 -->
            <el-table-column type="index"
                             label="#">
            </el-table-column>
            <el-table-column label="参数名称"
                             prop="attr_name">
            </el-table-column>
            <el-table-column label="操作">
              <template v-slot='scope'>
                <el-button type="primary"
                           icon="el-icon-edit"
                           size="mini"
                           @click="showEditDialog(scope.row.attr_id)">编辑</el-button>
                <el-button type="danger"
                           icon="el-icon-delete"
                           size="mini"
                           @click="removeParams(scope.row.attr_id)">删除</el-button>
              </template>
            </el-table-column>
          </el-table>
        </el-tab-pane>
        <!-- 静态属性 -->
        <el-tab-pane label="静态属性"
                     name="only">
          <el-button type="primary"
                     size="mini"
                     :disabled='isBtnDisable'
                     @click="addDialogVisible=true">添加参数</el-button>
          <!-- 静态属性表格 -->
          <el-table :data="onlyTableData"
                    border
                    stripe>
            <!-- 展开行 -->
            <el-table-column type="expand">
              <template v-slot='scope'>
                <el-tag v-for="(item,index) in scope.row.attr_vals"
                        :key="index"
                        closable
                        @close="handleClose(index,scope.row)">{{item}}</el-tag>
                <!-- 添加的文本框 -->
                <el-input class="input-new-tag"
                          v-if="scope.row.inputVisible"
                          v-model="scope.row.inputValue"
                          ref="saveTagInput"
                          size="small"
                          @keyup.enter.native="handleInputConfirm(scope.row)"
                          @blur="handleInputConfirm(scope.row)">
                </el-input>
                <!-- 添加属性按钮 -->
                <el-button v-else
                           class="button-new-tag"
                           size="small"
                           @click="showInput(scope.row)">+ New Tag</el-button>
              </template>
            </el-table-column>
            <!-- 索引行 -->
            <el-table-column type="index"
                             label="#">
            </el-table-column>
            <el-table-column label="属性名称"
                             prop="attr_name">
            </el-table-column>
            <el-table-column label="操作">
              <template v-slot='scope'>
                <el-button type="primary"
                           icon="el-icon-edit"
                           size="mini"
                           @click="showEditDialog(scope.row.attr_id)">编辑</el-button>
                <el-button type="danger"
                           icon="el-icon-delete"
                           size="mini"
                           @click="removeParams(scope.row.attr_id)">删除</el-button>
              </template>
            </el-table-column>
          </el-table>
        </el-tab-pane>
      </el-tabs>
    </el-card>
    <!-- 添加参数的对话框 -->
    <el-dialog :title="'添加'+(activeName==='many'?'动态参数':'静态属性')"
               :visible.sync="addDialogVisible"
               width="50%"
               @close="addDialogClosed">
      <el-form :model="addForm"
               :rules="addFormRules"
               ref="addFormRef"
               label-width="100px">
        <el-form-item :label="(activeName==='many'?'动态参数':'静态属性')"
                      prop="attr_name">
          <el-input v-model="addForm.attr_name"></el-input>
        </el-form-item>
      </el-form>
      <span slot="footer"
            class="dialog-footer">
        <el-button @click="daddDialogVisible = false">取 消</el-button>
        <el-button type="primary"
                   @click="addParams">确 定</el-button>
      </span>
    </el-dialog>
    <!-- 修改参数的对话框 -->
    <el-dialog :title="'修改'+(activeName==='many'?'动态参数':'静态属性')"
               :visible.sync="editDialogVisible"
               width="50%"
               @close="editDialogClosed">
      <el-form :model="editForm"
               :rules="addFormRules"
               ref="editFormRef"
               label-width="100px">
        <el-form-item :label="(activeName==='many'?'动态参数':'静态属性')"
                      prop="attr_name">
          <el-input v-model="editForm.attr_name"></el-input>
        </el-form-item>
      </el-form>
      <span slot="footer"
            class="dialog-footer">
        <el-button @click="editDialogVisible = false">取 消</el-button>
        <el-button type="primary"
                   @click="editParams">确 定</el-button>
      </span>
    </el-dialog>
  </div>
</template>

<script>
export default {
  name: 'Params',
  data () {
    return {
      // 商品分类列表
      catelist: [],
      // 级联选择框的配置
      label: 'cat_name',
      value: 'cat_id',
      chlidren: 'children',
      // 级联选择框双向绑定的数组
      selectedKeys: [],
      // 双向绑带被激活的页签名称（默认选中的页签）
      activeName: 'many',
      // 动态参数的数据
      manyTableData: [],
      // 静态参数的数据
      onlyTableData: [],
      addDialogVisible: false,
      // 添加属性的表单数据
      addForm: {
        attr_name: ''
      },
      // 添加属性的表单验证规则
      addFormRules: {
        attr_name: [
          { required: true, message: '请输入参数名称', trigger: 'blur' }
        ]
      },
      // 修改属性的表单数据
      editForm: {
        attr_name: ''
      },
      // 修改属性的对话框显示与隐藏
      editDialogVisible: false
    }
  },
  created () {
    this.getCateList()
  },
  methods: {
    // 获取所有的商品分类
    async getCateList () {
      const { data: res } = await this.$http.get('categories')
      if (res.meta.status !== 200) {
        return this.$message.error('获取商品分类失败！')
      }
      this.catelist = res.data
    },
    // 级联选择框选中会变化，触发的函数
    handleChange () {
      this.getParamsData()
    },
    // tab 页签点击事件的处理函数
    handleTabClick () {
      this.getParamsData()
    },
    // 获取参数的数据列表
    async getParamsData () {
      // 判断选中的是不是三级分类
      if (this.selectedKeys.length !== 3) {
        this.selectedKeys = []
        this.manyTableData = []
        this.onlyTableData = []
        return
      }
      // 根据所选分类的id和当前所处的面板，获取对象的数据
      const { data: res } = await this.$http.get(`categories/${this.cateId}/attributes`, { params: { sel: this.activeName } })
      if (res.meta.status !== 200) {
        return this.$message.error('获取参数列表失败！')
      }
      res.data.forEach(item => {
        item.attr_vals = item.attr_vals ? item.attr_vals.split(' ') : []
        item.inputVisible = false
        item.inputValue = ''
      })
      if (this.activeName === 'many') {
        this.manyTableData = res.data
      } else {
        this.onlyTableData = res.data
      }
    },
    // 监听添加对话框的关闭事件
    addDialogClosed () {
      this.$refs.addFormRef.resetFields()
    },
    // 获取添加的参数并提交
    addParams () {
      // 判断是否通过验证
      this.$refs.addFormRef.validate(async valid => {
        if (!valid) return
        const { data: res } = await this.$http.post(`categories/${this.cateId}/attributes`, { attr_name: this.addForm.attr_name, attr_sel: this.activeName })
        if (res.meta.status !== 201) {
          return this.$message.error('添加参数失败！')
        }
        this.$message.success('添加参数成功！')
        this.getParamsData()
        this.addDialogVisible = false
      })
    },
    // 点击按钮展示修改对话框
    async showEditDialog (id) {
      this.editDialogVisible = true
      const { data: res } = await this.$http.get(`categories/${this.cateId}/attributes/${id}`, { params: { attr_sel: this.activeName } })
      if (res.meta.status !== 200) {
        return this.$message.error('获取参数失败！')
      }
      this.editForm = res.data
    },
    // 监听修改对话框的关闭事件，重置修改表单
    editDialogClosed () {
      this.$refs.editFormRef.resetFields()
    },
    // 获取修改的参数并提交
    async editParams () {
      const { data: res } = await this.$http.put(`categories/${this.cateId}/attributes/${this.editForm.attr_id}`, { attr_name: this.editForm.attr_name, attr_sel: this.activeName })
      if (res.meta.status !== 200) {
        return this.$message.error('更新参数失败！')
      }
      this.$message.success('更新参数成功！')
      this.getParamsData()
      this.editDialogVisible = false
    },
    // 删除参数
    async removeParams (id) {
      const confirmResult = await this.$confirm('此操作将永久删除该参数, 是否继续?', '提示', {
        confirmButtonText: '确定',
        cancelButtonText: '取消',
        type: 'warning'
      }).catch(err => {
        return err
      })
      // 如果用户确认删除,则返回字符串confirm
      // 如果用户取消删除,则返回字符串cancel
      if (confirmResult !== 'confirm') {
        return this.$message.info('已取消删除')
      }
      const { data: res } = await this.$http.delete(`categories/${this.cateId}/attributes/${id}`)
      if (res.meta.status !== 200) {
        this.$message.error('删除参数失败！')
      }
      this.$message.success('删除参数成功！')
      this.getParamsData()
    },
    // 文本框失去焦点与按下enter键都会触发
    handleInputConfirm (row) {
      // 判断输入的东西是否符合要求
      if (row.inputValue.trim() === '') {
        row.inputValue = ''
        row.inputVisible = false
        return
      }
      // 符合要求，进行后面的操作
      row.attr_vals.push(row.inputValue.trim())
      this.saveAttrVals(row)
      row.inputValue = ''
      row.inputVisible = false
    },
    // 将对attr_vals的操作，保存到数据库
    async saveAttrVals (row) {
      // 发起操作，保存
      const { data: res } = await this.$http.put(`categories/${this.cateId}/attributes/${row.attr_id}`, { attr_name: row.attr_name, attr_sel: this.activeName, attr_vals: row.attr_vals.join(' ') })
      if (res.meta.status !== 200) {
        return this.$message.error('添加参数新标签失败！')
      }
    },
    // 点击显示input
    showInput (row) {
      row.inputVisible = true
      // 仅仅把input显示出来时，页面任然时button按钮，还没被重新渲染，所有需要这个回调函数
      // $nextTick作用：就是当页面上元素被重新渲染之后，才会指定回调函数中的代码
      this.$nextTick(_ => {
        this.$refs.saveTagInput.$refs.input.focus()
      })
    },
    handleClose (index, row) {
      row.attr_vals.splice(index, 1)
      this.saveAttrVals(row)
    }
  },
  computed: {
    // 如果按钮需要被警用，则返回true,否则false
    isBtnDisable () {
      if (this.selectedKeys.length !== 3) {
        return true
      }
      return false
    },
    // 当前选中的三级分类的id
    cateId () {
      if (this.selectedKeys.length === 3) {
        return this.selectedKeys[2]
      }
      return null
    }
  }
}
</script>

<style lang="less" scoped>
.cat_opt {
  margin: 15px 0;
}
.el-tag {
  margin: 10px;
}
.input-new-tag {
  width: 130px;
}
</style>
